<?php
//使用方法：将本文件拷贝到系统根目录下执行即可
set_time_limit(0);
if (isset($_GET['dir'])){ //设置文件目录

$basedir=$_GET['dir'];

}else{

$basedir = '.';

}

$auto = 1;

checkdir($basedir);

function checkdir($basedir){
	if ($dh = opendir($basedir)) {
	  while (($file = readdir($dh)) !== false) {
	   if ($file != '.' && $file != '..'){
		if (!is_dir($basedir."/".$file)) {
		 echo "filename: $basedir/$file ".checkBOM("$basedir/$file")." <br>";
		}else{
		 $dirname = $basedir."/".$file;
		 checkdir($dirname);
		}
	   }
	  }
	  closedir($dh);
	}
}

function checkBOM ($filename) {

global $auto;

$contents = file_get_contents($filename);

$charset[1] = substr($contents, 0, 1);
$charset[2] = substr($contents, 1, 1);
$charset[3] = substr($contents, 2, 1);
if (ord($charset[1]) == 239 && ord($charset[2]) == 187 && ord($charset[3]) == 191) {

  if ($auto == 1) {

   $rest = substr($contents, 3);

   rewrite ($filename, $rest);

   return ("<font color=red>BOM found, automatically removed.</font>");

  } else {

   return ("<font color=red>BOM found.</font>");

  }

}

else return ("BOM Not Found.");

}

function rewrite($filename, $data) {
	$filenum = fopen($filename, "w");
	flock($filenum, LOCK_EX);
	fwrite($filenum, $data);
	fclose($filenum);
}